Underground drain tanks are required at compressor stations for gas wells, gas pipelines, i.e. compressor stations and the like, to collect contaminants during wash-down. Presently, the tanks used are typically fibreglass and steel, however, it has been found that the tanks themselves often rust or collapse resulting in leakage into the soil. This presents an environmental problem, particularly because some of these tanks contain amino acids, hydrocarbons and hydrogen sulphides.
Thus, there is a need for a containment vessel for underground use that is long lasting, strong and does not corrode or rust. There is also a need for an underground tank which may be tested from time to time to ensure that leakage is not occurring into the ground and thus contamination of the soil does not occur.
At present there are both steel and fibreglass tanks available as containment vessels.. These tanks are built with double walls and some have leak detection monitoring systems. However, if a double walled tank develops a leak, the whole tank must be replaced.